Objective To investigate the expression of aquaporin-1（AQP-1） on pleura in rats with carrageenan-induced pleural effusion and explore the role of AQP-1 in effusion formation.Methods Fifty-six healthy Wistar rats were randomly divided into a normal control group and 6 pleuritis groups（6，12，24，36，48 and 72 h groups respectively）.The rat model of inflammatory pleurisy was induced by injecting l-Carrageenan into the pleural cavity.The expression of AQP-1 on pleura was detected with immunohistochemistry.The mRNA and protein expression of AQP-1 on visceral pleura and parietal pleura were measured by RT-PCR and Western blot assay respectively.The volume of pleural effusions were measured.Results The volume of pleural effusion was 2.10±0.22，4.10±0.15，4.40±0.36，3.20±0.27，2.60±0.18，0.12±0.02 mL in the 6，12，24，36，48 and 72 h pleuritis groups respectively.AQP-1 were mainly expressed on visceral and parietal pleural mesothelial cells and capillary endothelial cells，and significantly increased in all pleuritic rats The mRNA and protein expression of AQP-1 on parietal pleura increased after 6 h and reached peak level at 24 h in pleuritic groups.The mRNA and protein expression of AQP-1 on visceral pleura increased after 12 h and reached peak level at 24 h in pleuritic groups.The expression of AQP-1 on parietal pleura at 12 h and 24 h in pleuritic groups was correlated positively with the volume of pleural effusion（r=0.857，r=0.846，all Plt;0.01）.The expression of AQP-1 on visceral pleura at 24 h in pleuritic groups was positively correlated with the volume of pleural effusion（r=0.725，Plt;0.05）.Conclusion The expression of AQP-1 on pleura were increased in rats with e carrageenan-induced pleural effusion.AQP-1 may play a role in pleural fluid transportation in pleural effusion.
Objective To investigate the expression of aquaporin-1( AQP-1) in pleural mesothelial cells ( PMCs) and the influence of glucose thereupon. Methods Rat PMCs were isolated, cultured, and divided into two groups, ie. a glucose group, cultured with glucose of different concentrations for 24 hours,and a control group, cultured in D-MEM/ F-12 medium. The 100 mmol / L glucose group was administered at the time points of 6, 12, 18, and 24 hours respectively. RT-PCR and Western blotting were used to analyze the mRNA and protein expression of AQP-1. Results The absorbance values of AQP-1 protein expression were 54. 02 ±4. 61, 127. 84 ±9. 41, and 231. 62 ±22. 63, respectively in the PMCs treated with glucose of the concentrations of 50, 100, and 200 mmol / L, all significantly higher than those in the control group( 22. 45 ±2. 16, all P lt; 0. 01) . The absorbance values of AQP-1 protein expression were 24. 68 ±2. 56, 58. 68 ±3. 67, 89. 61 ±6. 62, and 113. 41 ±7. 65 in the PMCs treated with glucose of the concentration of 100 mmol / L after 6, 12, 18, and 24 hours, all significantly higher than those in the control group ( 11. 81 ±1. 45, P lt;0. 01) .Conclusions Glucose induces the expression of AQP-1 mRNA and protein. AQP-1 participates in the pleural fluid formation.
Objective To investigate the expression of aquaporin-1( AQP1 ) in visceral and parietal pleura in SD rats and to examine the effect of AQP1 on pleural fluid turnover. Methods Five groups( n = 24 ) of SD rats were randomly assigned to received intrapleural injection of dexamethasone,lipopolysaccharide, erythromycin, hypertonic saline and normal saline, respectively. The AQP1 protein in pleural was detected with immunohistochemistry. The mRNA expression of AQP1 under stimulations at different time points was measured by real time RT-PCR. Results AQP1 was immunolocalized predominantly to the microvessels and mesothelial cells of visceral and parietal pleura. The extent of AQP1expression in parietal pleura was less than that in visceral pleura[ ( 4. 14 ±1. 12) ×104 copy /μg vs ( 7. 43 ±2. 02) ×104 copy / μg, P lt;0. 05] . AQP1 expression increased at all phases in the dexamethasone group andthe hypertonic saline group, whereas decreased in the erythromycin group and the lipopolysaccharide group.Conclusion The stimulations of dexamethasone, lipopolysaccharide, erythromycin and hypertonic saline can significantly change the AQP1 expression in pleura, which indicate that AQP1 may contribute to the accumulation and clearance of pleuritic fluids.
Objective To investigate the expression of aquaporin-1( AQP-1) in pulmonary tissues of asthma mice and the effects of acetazolamide( AZ) on AQP-1 expression. Methods Forty C57BL/6 mice were randomly divided into five groups. Group A was treated with phosphate buffer as a non-asthmatic group.The mice in group B, C, D, and E were sensitized with ovalbumin( OVA) and challenged with aerosol OVA to establish asthma model. The mice in group B, C, and D were interperitoneally injected with AZ at doses of 300, 200, 100 mg/kg, respectively during the challenge period. Results ①Wet/dry weight ratio of lung tissues in group E was significantly higher than that in group A( P lt;0. 05) , while it was lower in B, C and D groups than group E. ②The total number of cells, the number of eosinophils, and interleukin-5( IL-5) inBALF of group E were higher than those in group A( P lt;0. 05) , and interferon-γ( IFN-γ) level was lower in group E than in group A ( P lt; 0. 05) . After AZ treatment, the total number of cells, the number of eosinophils, neutrophils and lymphocytes were significantly decreased( P lt; 0. 05) , which were positively correlated with the dose of AZ. ③AQP-1 were expressed in tracheal epithelium, microvascular endothelial cell and bronchial peripheral vascular bed, and the expression in group E was significantly higher than that in group A( P lt;0. 01) . AQP-1 expression was significantly decreased after the intervention of AZ ( P lt;0. 05) .The decrease was positively correlated with the dose of AZ. The expression of AQP-1 mRNA showed no significant difference among these groups( P gt;0. 05) . Conclusions AQP-1 was over-expressed in the lung tissue of mice with asthma. AZ can inhibit the expression of AQP-1 and relieve lung inflammatory cells infiltrationin a dose-dependent manner. It is the protein expression of AQP-1 not the AQP-1 mRNA which were significantly different in different groups, suggesting that AZ affected AQP-1 in the post-transcriptional stage.